Obsolete Names for ICS Units

The interval definitions in this timescale are derived from the following sources:

  • W. B. Harland, R. L. Armstrong, A. V. Cox, L. E. Craig, A. G. Smith and D. G. Smith. 1990. A Geologic Time Scale 1989. view
  • K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. view
  • J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 view
  • A. D. Barnosky, M. Holmes, R. Kirchholtes, E. Lindsey, K.C. Maguire, A.W. Poust, M.A. Stegner, J. Sunseri, B. Swartz, J. Swift, N.A. Villavicencio and G. Wogan. 2014. Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs). The Anthropocene Review I(3):225-242 view
  • F. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) view

There are 55 timescales which overlap this one. show

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 92 collections

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International Chronostratigraphic TimescaleObsolete Names for ICS UnitsAmmonite Chrons of North AmericaPermian of the Russian PlatformCambrian of West AvaloniaSilurian of North AmericaCambrian of KazakhstanCretaceous North American Land-Mammal AgesNorth American Land Mammal AgesCambrian EpochsEuropean Faunal Zones
QuaternaryHoloceneMeghalayanSaintaugustinean0
Santarosean0.0004
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate Pleistocene0.0117
Rancholabrean0.014
Chibanian0.129
Irvingtonian0.21
Calabrian0.774
Blancan1.4
GelasianMN 171.8
NeogenePliocenePiacenzianTertiary †MN 162.58
MN 153.2
Zanclean3.6
MN 144.2
Hemphillian4.7
MN 134.9
MioceneMessinian5.333
TortonianMN 127.246
MN 117.75
MN 108.7
Clarendonian9.4
MN 99.7
MN 7 + 811.1
Serravallian11.63
Barstovian12.5
MN 612.8 *
LanghianMN 513.82
BurdigalianMN 415.98
Hemingfordian16.3
MN 316.9
Arikareean18.5
MN 220
Aquitanian20.44
MN 122.4
PaleogeneOligoceneChattian23.03
Rupelian27.82
Whitneyan29.5
Orellan31.8
EocenePriabonianChadronian33.9
Duchesnean37
Bartonian37.71
Uintan39.7
Lutetian41.2
Bridgerian46.2
Ypresian47.8
Wasatchian50.5
Clarkforkian54.9
PaleoceneThanetian56
Tiffanian56.2
Selandian59.2
Torrejonian60.9
Danian61.6
Puercan63.8
CretaceousLate CretaceousMaastrichtianLancian/Edmontonian66
CampanianJudithian/Aquilan72.1
Santonian83.6
Coniacian86.3
Turonian89.8
Cenomanian93.9
Early CretaceousAlbian100.5
Aptian113
Barremian121.4
Hauterivian125.77
Valanginian132.6
Berriasian139.8
JurassicLate JurassicTithonian145
Kimmeridgian149.2
Oxfordian154.8
Middle JurassicCallovian161.5
Bathonian165.3
BajocianEpizigzagiceras168.2
Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense168.4
AalenianHowelli/Scissum/Westermanni170.9
Early JurassicToarcianYakounensis/Hillebrandti/Crassicosta174.7
Planulata179.3 *
Arnioceras arnouldi179.8 *
Kanense181.3 *
Carlottense182.3 *
Kunae183.5 *
Pliensbachian184.2
Freboldi185.1 *
Whiteavesi/ImlayiTetraspidoceras186.2 *
189.2 *
Plesechioceras harbledownense/Asteroceras varians/CoronicerasCanadensis190.3 *
Sinemurian192.9
PseudaetomocerasPsiloceras196.4 *
Franziceras/Euphyllites196.5 *
Hettangian199.5
TriassicLate TriassicRhaetian201.4
Norian208.5
Carnian227
Middle TriassicLadinian237
Anisian242
Early TriassicOlenekian247.2
Induan251.2
PermianLopingianChanghsingian251.902
WuchiapingianLongtanian †254.14
TatarianVyatkian256.8 *
GuadalupianCapitanianSeverodvinian259.51
WordianUrzhumian264.28
RoadianKazanianPovolzhian266.9
Sokian270.7 *
CisuralianKungurianKungurianIrenian/Ufimian273.01
Filipovian276.5 *
Saraninian280.1 *
ArtinskianArtinskianSarginian283.5
Irginian285.9 *
Burtsevian287.8 *
SakmarianSakmarianSterlitamakian290.1
Tastubian291.7 *
AsselianAsselianShikhanian293.52
Uskalykian294.8
Surenian297.5
CarboniferousPennsylvanianGzhelian298.9
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennian358.9
Frasnian372.2
Middle DevonianGivetian382.7
Eifelian387.7
Early DevonianEmsian393.3
Pragian407.6
Lochkovian410.8
SilurianPridoliCayugan419.2
Niagaran422.5 *
LudlowLudfordian423
Gorstian425.6
WenlockHomerianLockportian427.4
Sheinwoodian430.5
LlandoveryTelychianOntarian433.4
Aeronian438.5
Alexandrian438.7 *
MedinanClinton440.1 *
440.7 *
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantian443.8
Katian445.2
Sandbian453
Middle OrdovicianDarriwilian458.4
Dapingian467.3
Early OrdovicianFloian470
TremadocianUngurian477.7
CambrianFurongianStage 10BatyrbaianLate Cambrian485.4
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
MiaolingianGuzhangianSeries 3 †AyusokkanianMiddle Cambrian497
Arcadian498.4
499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanStage 5 †504.5
505.3
Series 2Stage 4BranchianEarly Cambrian509
Toyonian510 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
Placentian517.1
TerreneuvianStage 2Tommotian521
525.5
Fortunian529
538.8